.mob_lb img:hover{transform:none}
.banner_lb{ width:1000px; margin:0 auto}
div.mob_lb {
    width:100%;
    margin: auto;
    position: relative;
}
div.mob_lb img {
    width:100%;
    height: auto;
    vertical-align: bottom;
}
.dote {
    position: absolute;
    bottom: 0; left:0; right:0; margin:auto;
    height: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
}
.dote>span {
    display: inline-block;
    height: 10px;
    width: 10px;
    border-radius: 50%;
    margin: 2px;
}
span[class^="jian"]{
    position: absolute;

    margin-top: -50%;
    display: inline-block;
    height: 50px;
    width: 50px;
    border-radius: 80%;
    margin: 2px;
    background-color: rgba(0, 0, 0, 0.6);
    text-align: center;
    line-height: 50px;
    color: white; font-size:24px;top:0; bottom:0; margin:auto;
}
.jianleft{
    left: 0;
}
.jianright{
    right: 0;
}